[GHC] #7468: incorect waiting for packets on UDP connections.

[GHC]

#7468: incorect waiting for packets on UDP connections.
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Reporter:  ET                           |          Owner:                  
    Type:  bug                          |         Status:  new             
Priority:  normal                       |      Component:  libraries/base  
 Version:  7.4.1                        |       Keywords:  UDP packet loss.
      Os:  Linux                        |   Architecture:  Unknown/Multiple
 Failure:  Incorrect result at runtime  |      Blockedby:                  
Blocking:                               |        Related:                  
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 Preconditions:
 Have an UDP server.
 Transform the socket into a handle.
 call hWaitForInput.
 When it returns True.
 call recv to read the datagram.

 Expected result:
 it will wait for a package with the hWaitForInput.
 when the package arrives (withing the timeout).
 it will read it in the buffer.
 (this is how it works in HUGS).

 Actual result:
 hWaitForInput consumes the package (I think).
 recv will block until the next package arrives.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7468>
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